CVE-2026-31412
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_mass_storage: Fix potential integer overflow in check_command_size_in_blocks() The `check_command_size_in_blocks()` function calculates the data size in bytes by left…
Does this matter?
Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_mass_storage: Fix potential integer overflow in check_command_size_in_blocks() The `check_command_size_in_blocks()` function calculates the data size in bytes by left shifting `common->data_size_from_cmnd` by the block size (`common->curlun->blkbits`). However, it does not validate whether this shift operation will cause an integer overflow. Initially, the block size is set up in `fsg_lun_open()` , and the `common->data_size_from_cmnd` is set up in `do_scsi_command()`. During initialization, there is no integer overflow check for the interaction between two variables. So if a malicious USB host sends a SCSI READ or WRITE command requesting a large amount of data (`common->data_size_from_cmnd`), the left shift operation can wrap around. This results in a truncated data size, which can bypass boundary checks and potentially lead to memory corruption or out-of-bounds accesses. Fix this by using the check_shl_overflow() macro to safely perform the shift and catch any overflows.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.17% probability · 7th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-190
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/228b37936376143f4b60cc6828663f6eaceb81b5Patch
- https://git.kernel.org/stable/c/3428dc5520c811e66622b2f5fa43341bf9a1f8b3Patch
- https://git.kernel.org/stable/c/387ebb0453b99d71491419a5dc4ab4bee0cacbacPatch
- https://git.kernel.org/stable/c/8479891d1f04a8ce55366fe4ca361ccdb96f02e1Patch
- https://git.kernel.org/stable/c/91817ad5452defe69bc7bc0e355f0ed5d01125ccPatch
- https://git.kernel.org/stable/c/ce0caaed5940162780c5c223b8ae54968a5f059bPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.